Modern automotive vehicles have an increasing content of electrical and electronic devices that require wires with electrical terminals at the ends for their use in vehicles. This increased electrical content in the vehicle occurs at the same time that there is also an increase in the number of components attached or fixed around the engine in the underhood engine compartment of the vehicle. This congestion in the engine compartment reduces ambient cooling of the compartment area and leads to higher temperatures in the compartment. Because the operating engine causes or experiences some vibration, underhood electrical connections on passenger cars and trucks can be exposed to temperatures above 150.degree. C., combined with severe vibration. Some electrical terminal contact materials, such as, for example, gold, have high softening temperatures and can withstand operating temperatures above 150.degree. C. However, high vibration can quickly degrade their contact properties. Vibration can cause microscopic relative movement at electrical contact interfaces that quickly wears away existing contact materials. The result is unstable or intermittent connection resistance, which can adversely affect vehicle performance.
The vibration resistance of a connector can be improved by minimizing the relative movement at contact interfaces. This normally requires improved connector locks, seals and wiring harness strain relief features, all of which add to the cost of the wiring of the vehicle. An alternative to minimizing terminal movement is to develop electrical contact materials with improved wear and temperature resistance. It is an object of this invention to provide a new terminal coating material with outstanding wear resistance and good high temperature electrical performance.